Obesity in 30's increases risk of dementia in later life

A new study has found that people who are obese in their early to mid-life face more risk of dementia in their later lives, with the ones in their 30's facing triple the risk.

The researchers used the anonymised data from hospital records for the whole of England for the period 1999-2011, and data in which obesity had been recorded were then searched for any subsequent care for, or death from, dementia.

During the study period, 451 232 of those admitted to hospital in England were diagnosed with obesity, 43 percent of whom were men.

The analysis revealed an incremental decrease in overall risk of hospital admission for dementia the older a person was when a diagnosis of obesity was first recorded, irrespective of gender.

For those aged 30-39, the relative risk of developing dementia was 3.5 times higher than in those of the same age who were not obese. For those in their 40s, the equivalent heightened risk fell to 70 percent more; for those in their 50s to 50 percent more; and for those in their 60s to 40 percent more.

People in their 70s with obesity were neither at heightened or lowered risk of developing dementia, while those in their 80s were 22 percent less likely to develop the disease, the findings indicated.

There were some age differences between the risk of developing vascular dementia or Alzheimer's disease, with those in their 30s at greater risk of both. A diagnosis of obesity in the 40s through to the 60s was associated with an increased risk of vascular dementia, while the risk of Alzheimer's disease was lower in those diagnosed with obesity from their 60s onwards.

The researchers concluded that while obesity at a younger age was associated with an increased risk of future dementia, obesity in people who had lived to about 60-80 years of age seemed to be associated with a reduced risk.